It can be desirable to communicate rotation between a first shaft and second shaft extending away from one another at an angle. The first shaft can be a driving shaft and the second shaft can be a driven shaft. The shafts can be connected to one another with a single universal joint, an arrangement known as a Hooke joint. However, one drawback of a Hooke joint is that the driven shaft will not rotate at a uniform angular velocity. In particular, during revolution the driven shaft will experience angular acceleration and deceleration in response to relatively constant angular velocity of the driving shaft.
A cardan joint engages two shafts with respect to another with an intermediate, revolving coupling member. First and second universal joints connect the first and second shafts, respectively, to the intermediate coupling member. The cardan joint arrangement imparts constant velocity to the driven shaft. The cardan joint can include a centering plate positioned in the intermediate coupling member that engages both shaft ends to generally maintain the same output angle of the driven shaft as the input angle of the driving shaft. The centering plate can define an aperture for receiving rounded ends of the shafts. Alternatively, the centering plate can define rounded projections receivable in apertures defined by the shafts.
Users of cardan joints can require a product for applications having high joint angles and/or a joint to enable the angles defined between each shaft and the intermediate coupling member to be equal to minimize peak-to-peak torque variation. These two design parameters are primarily driven by vehicle packaging issues. In these applications, the current production universal joints may not work because of limitations in angular capability and phasability.